Linux系统分区（硬盘GPT分区与MBR分区的转换）

一.MBR分区与GPT分区的区别

二.MBR分区方式

1.主分区

主分区表记录分区的信息并可以直接使用的分区

2.扩展分区

主分区表记录的分区，不可直接使用，只是逻辑分区容器

3.逻辑分区

扩展分区之上划分的分区叫做逻辑分区

4.分区方法

[root@rhel7 ~]# fdisk /dev/sdb
Welcome to fdisk (util-linux 2.23.2).

Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.


Command (m for help): n      					##新建
Partition type:
   p   primary (0 primary, 0 extended, 4 free)	##主分区
   e   extended									##扩展分区
Select (default p): p							##建立主分区
Partition number (1-4, default 1): 1			##分区表位置
First sector (2048-20971519, default 2048): 	##分区起始位置（推荐使用默认）
Using default value 2048
Last sector, +sectors or +size{K,M,G} (2048-20971519, default 20971519): +100M     	##分区结束位置
Partition 1 of type Linux and of size 100 MiB is set

Command (m for help): p    						##显示分区表

Disk /dev/sdb: 10.7 GB, 10737418240 bytes, 20971520 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0x0002db10

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1            2048      206847      102400   83  Linux

Command (m for help): wq  ##退出保存，如果直接q表示退出不保存
The partition table has been altered!

Calling ioctl() to re-read partition table.
Syncing disks.
[root@rhel7 ~]# partprobe			##同步分区表
Warning: Unable to open /dev/sr0 read-write (Read-only file system).  /dev/sr0 has been opened read-only.
[root@rhel7 ~]# mkfs.xfs /dev/sdb1  ##格式化设备为xfs文件系统（相当与在/dev/sdb1上安装设备管理软件）
mkfs.xfs: /dev/sdb1 appears to contain an existing filesystem (xfs).
mkfs.xfs: Use the -f option to force overwrite.

三.MBR分区方式转换成GPT

[root@rhel7 ~]# parted /dev/sdb
GNU Parted 3.1
Using /dev/sdb
Welcome to GNU Parted! Type 'help' to view a list of commands.

(parted) mklabel
                                                              
New disk label type? gpt
Warning: The existing disk label on /dev/sdb will be destroyed and all data on this disk will be lost. Do you want to continue?

Yes/No? yes                                                                                                                                       

(parted) quit                                                             
Information: You may need to update /etc/fstab.

四.GPT分区方式

[root@rhel7 ~]# fdisk /dev/sdb
WARNING: fdisk GPT support is currently new, and therefore in an experimental phase. Use at your own discretion.
Welcome to fdisk (util-linux 2.23.2).

Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.

Command (m for help): n     				##新建
Partition number (1-128, default 1): 1		##分区表位置
First sector (34-20971486, default 2048): 	##分区起始位置（推荐使用默认）
Last sector, +sectors or +size{K,M,G,T,P} (2048-20971486, default 20971486): +100M                ##分区结束位置
Created partition 1

Command (m for help): p						##显示分区

Disk /dev/sdb: 10.7 GB, 10737418240 bytes, 20971520 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: gpt					  ##分区方式为gpt
Disk identifier: 76E1957A-23A1-4FCB-8880-0DBAA9B5823A

#         Start          End    Size  Type            Name
 1         2048       206847    100M  Linux filesyste 

Command (m for help): wq				##退出保存
The partition table has been altered!

Calling ioctl() to re-read partition table.
Syncing disks.

五.GPT分区方式转换成MBR

[root@rhel7 ~]# parted /dev/sdb
GNU Parted 3.1
Using /dev/sdb
Welcome to GNU Parted! Type 'help' to view a list of commands.

(parted) mklabel

New disk label type? msdos                                                                                                                                      
Warning: The existing disk label on /dev/sdb will be destroyed and all
data on this disk will be lost. Do you want to continue?

Yes/No? yes 
                                                                                                                                             
(parted) quit                                                                      
Information: You may need to update /etc/fstab.